Radiator



F, B. HERZ Aug. 31, 1937.

RADIATOR Filed Nov. 4

/N VEA T() A FERDINAND B-HERZ BY waxww 4 I ulm Patented Aug. 31, 1937RADIATOR Ferdinand B. Herz, Detroit, Mich., assgnor Vto Borg-WarnerCorporation, Chicago, Ill., a corporation of Illinois ApplicationNovember 4, 1935, Serial No. 48,228

4 Claims.

The invention relates to heat exchange devices commonly termedradiators, such as used in connection with cooling systems for internalcombustion engines. It is the object of the invention to obtainincreased efliciency and to this end the invention consists of theconstruction as hereinafter set forth.

In the drawing:

Figure 1 is a horizontal section through a portion of a radiator of myimproved construction;

Figure 2 is a perspective View thereof;

Figure 3 is an enlarged vertical se-ction on line 3-3 of Figure 1;

Figure 4 is an enlarged vertical transverse section;

Figures 5, 6 and '7 are views similar to Figure 1 showing modifiedconstructions;

Figures 6A and 7A are cross-sections respectively on the lines. (iA-6Aand lA-lA of Figures 6 and 7;

Figure 7B is a section on line IB- 1B of Figure 7.

Heat exchange devices of the type above referred to operate almostexclusively on the principle of air convection. For this, it isessential that the air which is to dissipate the heat should come inactual contact with the metallic surface through which the heat isconducted from the water tubes. It is usual to provide in addition tothe tube surface, fins of thin metal through which the tubes pass andwhich are closely spaced to form therebetween air channels extendingfrom front to rear. These ns have `been variously constructed toincrease the amount of contact surface with the air and to change thedirection of the current from a strictly rectilinear course with theobject of increasing eiciency. It is, however, necessary to avoid anyobstruction which will lessen the quantity of air passing through theradiator in a given time interval as this will have the effect ofdecreasing efficiency.

It is the object of the present invention to obtain a fin and tubeconstruction which offers but slight resistance to the free flow of airthrough the radiator, but which produces a high degree of turbulence inthe currents between the fins and tubes, the construction being asfollows.

The tubes A are of a flattened elongated crosssection and are arrangedin staggered or off-set rows. B are the fins which extend transverselyand are apertured for the passage of the tubes therethrough. Each ofthese fins is formed with rounded embossments C, preferably asubstantially spherical segment, and so arranged that each tube willextend diametrically acrossk one of these embossments. The metal struckout in forming the tube apertures constitutes a depending fia-nge Dsurrounding and closely fitting the tubes to increase the thermalContact.

With the construction as just described it will' be evident that thesuperposed fins will extend in parallelism to each other and withoutrestriction of the cross-section of the air currents passingtherebetween, nevertheless, the air is caused to undulate bothvertically and laterally thereby producing a churning action whichbrings all portions of the current at one time or another into actualcontact with the metal surface. There is also a division of the aircurrents as they pass the successive tubes from front to rear. Thus, asshown in Figure 1, the air passing between the front tubes A' and A2must rise over the embossments C and C2 with the exception of theportion which travels between these embossments. Upon reaching the tubeA3 in the next row the current is divided a small portion indicated bythe arrow E passing between the tubes A vand A3 and the roundedembossments thereof, while another portion indicated by the arrow Fpasses through the larger space between the embossments C2 and C3. Thisaction is repeated in passing the successive rows of tubes. The spa-cefor the small current E forms in effect a Venturi passage being firstrestricted and then enlarged and with the result of increasing thevelocity of the air passing therethrough. This high velocity current iscommingled with the current passing on the opposite side of the tube Athereby causing further turbulence.

The modied constructions shown in` Figures 5 to 7 inclusive, all embodythe features described in connection with Figures 1 to 4, but have someadditional features. Thus in Figure 5, there is a further embossment Gbetween the adjacent portions of the embossments C', C2. In Figure 6,the embossments C4 instead of being -circular are of greater length thanwidth. There is also an embossment H arranged between the embossments C4of adjacent tubes in the same row forming the cross-section shown inFigure 6A. In Figure 7, a continuous embossment I extends betweenadjacent tubes being of arcuate crosssection of diminishing radius fromthe tubes to the center therebetween, as shown in Figure 7B. With al1 ofthese modified constructions, an oscillatory movement will be impartedto the air during its passage through the radiator and there is also adividing of the currents around each tube. Such structures have provento be very eflicient in rapidly dissipating the heat and all can beeasily manufactured at a low cost.

What I claim as my invention is:

1. In a radiator of the tube and fin type, a

5 plurality of rows of parallelly arranged tubes elongated incross-section in the direction of air flow, and parallel ns extendingtransversely of said tubes provided with segmental spherical enbossments, each tube extending across the cen- 10 ter of the crest of anembossment, and the tubes and embossrnents in successive rows beingolf-setA in relation to each other.

2. In a radiator of the tube and n typ`e,'ra'H plurality of rows ofparallelly arranged tubes 15 elongated in cross-section in the direction'-of" air ow, and parallel ns extending transversely of said tubesprovided with segmental spherical embossments registering with therespective tubes to be crossed diametrically thereby, the

20- tubes and embossments in successive rows being elongated incross-section in the direction of air ilow, and parallel fins extendingtransversely of said tubes provided with segmental spherical embossmentsregistering with the respective tubes to be diametrically crossedthereby and with additional embossments between the embossments ofadjacent tubes in the saine row.

4. In a radiator of the tube and n type, a plurality of rows ofparallelly arranged tubes elongated in cross-section in the direction ofair ow, and parallel fins extending transversely of said tubes providedwith segmental spherical embossments registering with the respectivetubes so as to be diametrically crossed thereby, the tubes andembossments in successive rows being oiT-set'in relation to each other,and the tubes of said rows longitudinally overlapping whereby said tubesand embossments form a Y substantially Venturi-shaped restricted airpassage therebetween with a larger air passage on the opposite side ofthe succeeding tube and with the Venturi passage of one tube in each rowdischarging into the larger passage of an adjacent tube in the same row.

FERDINAND B. HERZ.

